The present invention relates to an inflatable external airbag system of a motor vehicle for protection of people outside of the motor vehicle in the event of a collision between the motor vehicle and a pedestrian, a bicycle, or a motorcycle. The system is configured to prevent the pedestrian, a rider of the bicycle, or a rider of the motorcycle (hereinafter generally referred to as “pedestrian”) from directly colliding with a windshield, thereby protecting the pedestrian.
As a motor vehicle collides with a pedestrian, a bicycle, or a motorcycle, the pedestrian, a rider of the bicycle, or a rider of the motorcycle, may be hit at his or her lower body with a front body of the motor vehicle so as to jump onto a hood covering the top of the vehicle front body. As a result, the pedestrian may suffer a secondary collision with the windshield of the motor vehicle.
Japanese Unexamined Utility Model Publication No. H06-74533 discloses an inflatable external airbag system as a pedestrian protective airbag system of which an airbag is deployed from a rear portion of a hood along an outer surface of the windshield, thereby preventing a pedestrian from directly colliding with a windshield of a motor vehicle. Hereinafter, referring to FIGS. 5(a)-5(c), the inflatable external airbag system of this publication will be described.
As shown in FIG. 5(a), the inflatable external airbag system 100 includes an airbag 102, a gas generator (inflator) 104 for inflating the airbag 102. The gas generator 104 is disposed in a cowl top 108, having a container shape, located beneath a windshield (front windscreen glass) 106 of the motor vehicle. The airbag 102 is folded and accommodated in the cowl top 108. The cowl top 108 is adjacent to the rear end (as seen in the longitudinal direction of the vehicle body) of a hood 110 covering the top of the vehicle front body.
The cowl top 108 comprises: a cowl top outer panel 112 exposed on the top of the vehicle front body, a cowl top inner panel 114 composing the bottom of the cowl top 108. The cowl top outer panel 112 is provided with an opening for allowing the airbag 102 to be deployed over the top of the vehicle front body. The opening is positioned above the airbag 102 accommodated in the cowl top 108. In the normal state, a lid 116 is disposed to close the opening.
The front end of the motor vehicle such as a front bumper 118 is provided with a contact detection sensor 120 for sensing a collision between the motor vehicle during running and a pedestrian, a bicycle, or a motorcycle. In the inflatable external airbag system 100 is structured so that, as the contact detection sensor 120 senses the collision, the gas generator 104 is triggered to introduce gas into the airbag 102, thereby inflating the airbag 102.
As the motor vehicle equipped with the inflatable external airbag device 100 collides with a pedestrian, a bicycle, or a motorcycle, the contact detection sensor 120 senses the collision, gas is introduced from the gas generator 104 to the inside of the airbag 102, thereby inflating the airbag 102. Then, the airbag 102 pushes to open the lid 116 attached to the opening of the cowl top 108 to expand over the top of the vehicle front body and is deployed from the rear portion of the hood 110 along the outer surface of the windshield 106 as shown in FIG. 5(c).
Therefore, even if the pedestrian, who is hit onto the hood 110 as a result of the collision with the motor vehicle, plunges into the windshield 106, the airbag 102 receives the pedestrian and thus prevents the pedestrian from directly colliding with the windshield 106.
In the inflatable external airbag system 100, the airbag 102 is easily affected by wind direction and wind pressure because the airbag 102 is exposed to air around the top of the front body of the running vehicle when the airbag 102 is deployed from the rear portion of the hood 110 along the outer surface of the windshield 106. Accordingly, it may sometimes be difficult to deploy the airbag 102 into a desired position.